That does not sound very promising if you didn't make any backups of your data.

Do you still have the old PC, or the hard drive from that PC, physically available to you.

I do have the old computer and have not wiped it yet. But i did uninstall Firefox.

On your old computer -- Windows, I assume? -- please try this, because unless you took special measures, a simple uninstall of Firefox doesn't remove your data.

Type or paste the following shortcut into the Windows "Run" dialog or into the system search box and press Enter to execute it. It should launch a folder in Windows Explorer:

%APPDATA%\Mozilla\Firefox\Profiles

If that path still exists, you can drill down into the profile folder(s) and look for a folder named bookmarkbackups that should contain compressed files with a .jsonlz4 extension, each indicating the date they were made and how many bookmarks+folders they contain.

The profile folder has other old data such as saved passwords that might be valuable. This article describes a lot of the files users often want to recover: Restore bookmarks, passwords and data from an old Firefox profile.

If that method doesn't work, could you indicate what version of Windows it was?